#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=1000;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
char str[110][maxn];
LL len[110];
int main(void)
{
  	///cin.tie(0);std::ios::sync_with_stdio(false);
    LL n;cin>>n;
    n=n*2-1;
    for(LL i=1;i<=n;i++){

    }

    for(LL i=1;i<=n;i++){
        cout<<"len["<<i<<"]="<<len[i]<<"\n";
        for(LL j=1;j<=len[i];j++){
            cout<<str[i][j]<<" ";
        }
        cout<<"\n";
    }
return 0;
}
